4 * Inline functions for unaligned memory accesses.
6 * The author dedicates this file to the public domain.
7 * You can do whatever you want with this file.
10 #ifndef _WIMLIB_UNALIGNED_H
11 #define _WIMLIB_UNALIGNED_H
13 #include "wimlib/compiler.h"
14 #include "wimlib/endianness.h"
15 #include "wimlib/types.h"
17 #define DEFINE_UNALIGNED_TYPE(type) \
18 struct type##_unaligned { \
20 } _packed_attribute; \
23 load_##type##_unaligned(const void *p) \
25 return ((const struct type##_unaligned *)p)->v; \
29 store_##type##_unaligned(type val, void *p) \
31 ((struct type##_unaligned *)p)->v = val; \
34 DEFINE_UNALIGNED_TYPE(u16);
35 DEFINE_UNALIGNED_TYPE(u32);
36 DEFINE_UNALIGNED_TYPE(u64);
37 DEFINE_UNALIGNED_TYPE(le16);
38 DEFINE_UNALIGNED_TYPE(le32);
39 DEFINE_UNALIGNED_TYPE(le64);
40 DEFINE_UNALIGNED_TYPE(be16);
41 DEFINE_UNALIGNED_TYPE(be32);
42 DEFINE_UNALIGNED_TYPE(be64);
43 DEFINE_UNALIGNED_TYPE(size_t);
44 DEFINE_UNALIGNED_TYPE(machine_word_t);
46 #define load_word_unaligned load_machine_word_t_unaligned
47 #define store_word_unaligned store_machine_word_t_unaligned
50 copy_word_unaligned(const void *src, void *dst)
52 store_word_unaligned(load_word_unaligned(src), dst);
55 static inline machine_word_t
60 BUILD_BUG_ON(WORDSIZE != 4 && WORDSIZE != 8);
65 v |= v << ((WORDSIZE == 8) ? 32 : 0);
70 get_unaligned_u16_le(const void *p)
74 if (UNALIGNED_ACCESS_IS_FAST) {
75 v = le16_to_cpu(load_le16_unaligned(p));
86 get_unaligned_u32_le(const void *p)
90 if (UNALIGNED_ACCESS_IS_FAST) {
91 v = le32_to_cpu(load_le32_unaligned(p));
97 v |= (u32)p8[2] << 16;
98 v |= (u32)p8[3] << 24;
104 put_unaligned_u16_le(u16 v, void *p)
106 if (UNALIGNED_ACCESS_IS_FAST) {
107 store_le16_unaligned(cpu_to_le16(v), p);
110 p8[0] = (v >> 0) & 0xFF;
111 p8[1] = (v >> 8) & 0xFF;
116 put_unaligned_u32_le(u32 v, void *p)
118 if (UNALIGNED_ACCESS_IS_FAST) {
119 store_le32_unaligned(cpu_to_le32(v), p);
122 p8[0] = (v >> 0) & 0xFF;
123 p8[1] = (v >> 8) & 0xFF;
124 p8[2] = (v >> 16) & 0xFF;
125 p8[3] = (v >> 24) & 0xFF;
129 #endif /* _WIMLIB_UNALIGNED_H */